Journal of Electrochemical Science and Engineering
Journal of Electrochemical Science and Engineering (ISSN 1847-9286) is an international, peer-reviewed open-access journal devoted to the rapid dissemination of new and original scientific results in all areas of electrochemical science, engineering, technology and material engineering.
International Association of Physical Chemists (IAPC)
Electrocoagulation as an effective all-in-one wastewater treatment: a critical review
Electrocoagulation has emerged as a promising alternative for the treatment of wastewater from a wide range of sources. Interest in this technology has grown due to its several advantages, including a small footprint, cost-effectiveness, and environmental sustainability. In contrast, conventional wastewater treatment methods that rely primarily on biological processes often exhibit limited removal of emerging contaminants, highlighting the need for more efficient and versatile treatment alternatives. This review article provides an in-depth discussion of the application of electrocoagulation technology for wastewater treatment, with a specific focus on its performance in real wastewater matrices across industrial, municipal, and agricultural case studies, including evidence from case studies demonstrating its use on a large scale. It examines key factors that influence process performance and presents the governing equations that determine the technology's efficiency and applicability. A key contribution of this review is the integrated analysis of reactor design, operational parameters, and emerging hybrid electrocoagulation (EC) systems, such as EC coupled with advanced oxidation processes (EC-AOP) and membrane processes (EC-membrane), highlighting recent technological advancements that improve treatment efficiency while reducing energy consumption. The review also addresses techno-economic considerations and synthesizes findings from life-cycle assessment studies, revealing critical trade-offs between environmental benefits, such as reduced eutrophication potential, and limitations including increased ecotoxicity. Finally, the article identifies key research gaps and highlights the potential of replacing fossil fuel-based energy inputs with renewable energy sources as well as the importance of electrode optimization and sludge valorisation strategies to improve the overall sustainability and scalability of electrocoagulation systems.
Copyright (c) 2026 Kiran Tota-Maharaj, Nasrin Rastinifard, Aya Gallab, Usman M. Ismail, Chedly Tizaoui, Hazem Gouda, Upaka Rathnayake, Abraham Negaresh https://creativecommons.org/licenses/by/4.0
Synergistic heterogeneous electro-Fenton process using iron-loaded bentonite for binary dyes degradation from wastewater
This study examines the impact of operational parameters on the performance of a heterogeneous electro-Fenton process for removing a binary mixture of malachite green (MG) and methylene blue (MB) using iron-loaded bentonite clay (Fe-Bent.) particles as a heterogeneous catalyst. The effects of current density (j), Fe-Bent.* dosage (Bent. quantity variable) and Fe*-Bent. dosage (iron concentration variable), were investigated. Brunauer-Emmett-Teller analysis, X-ray diffraction, X-ray fluorescence and scanning electron microscopy were used to extensively evaluate the synthesized catalyst, confirm­ing the effective incorporation and uniform distribution of iron within the bentonite clay. The results showed that increase of j enhanced dye removal efficiency to over 95 % for MG and 90 % for MB at 20 mA cm-². Furthermore, increasing the dose of Fe-Bent.* from 1 to 3 g improved the overall removal efficiency, although this was accompanied by a decrease in adsorption capacity and a deviation from ideal kinetic behaviour at higher loadings. Fe*-Bent. dosage with a variable iron concentration from (0.1 to 0.2 mM) exhibited the highest removal efficiency, while increasing to 0.3 mM resulted in decreased process performance. The comparison results showed that the electro-Fenton process alone achieved limited removal, whereas bentonite adsorption alone provided high but incomplete removal. In contrast, the heterogeneous electro-Fenton process achieved the highest efficiency (98.06 % for MG and 91.14 % for MB, with COD values of 84.53 % for MG and 79.82 % for MB), with the lowest iron leaching (<0.1 ppm), well below regulatory limits. These results demonstrate the clear advantage of the heterogeneous electro-Fenton process for efficient and environmentally friendly removal of mixed dye pollutants.
Copyright (c) 2026 Hind H. Thwaini, Zahraa M. Hameed, Rasha H. Salman https://creativecommons.org/licenses/by/4.0
Carboxylate-controlled electron transfer in Bacillus clausii J1G-0%B halophilic microbial fuel cells
Microbial fuel cells (MFCs) provide a cohesive approach to treating hypersaline wastewater and generating renewable energy. This research assessed the efficacy of halophilic Bacillus clausii J1G-0%B supplemented with acetate, lactate, or citrate at doses of 10, 30 and 50 mM. The half-cell investigation included cyclic voltammetry, diagnostics of the rate-determining step, electron transfer rate constant (kₛ), pH profiles, and ammonia buildup. Comprehensive cell testing, including assessments of output voltage, peak power density, and biofilm mass, was also performed. In comparison to the control, all carbon sources enhanced the electrochemical response by 184.56 to 378.23 %, due to bacterial-electrode electron transfer, diffusion-limited kinetics, and the involvement of cytochromes a₃, b, c and/or c₁ in B. clausii. The MFC system generated an average voltage ranging from 33.64 to 77.87 mV and achieved a maximum power density between 19.19±3.11 and 58.16±3.54 mW m-². Within the tested range, the highest acetate concentration (50 mM) produced the largest electrochemical response, yielding kₛ of 1.888±0.002 s⁻¹, an average voltage of 486.94 mV, and a power density of 58.16±3.54 mW m-². The results demonstrate that targeted carboxylate supplementation significantly improves electron transport and energy recovery in high-salinity microbial fuel cells, underscoring its viability for waste cleanup and energy generation during energy shortages and environmental contamination.
Copyright (c) 2026 Marcelinus Christwardana, Aprilia Budiarti, Mukhammad Asy'ari https://creativecommons.org/licenses/by/4.0
Electroless cobalt coating of BNi-2 powders: process development and characterization
Electroless cobalt deposition and examination of how cobalt enrichment on the particle surface modifies the chemical composition and thermal behaviour of the commercial BNi-2 brazing alloy powder was investigated in this study. A multi-step surface preparation sequence involving oxide removal, Sn-based sensitization, and Pd activation was employed prior to cobalt deposition in an alkaline CoSO₄-NaH₂PO₂ bath. A design of experiments approach was used to evaluate the influence of plating temperature, cobalt sulphate concentration, hypophosphite concentration, and coating time on cobalt uptake. ICP-OES analyses showed that cobalt incorporation increased from 1.1 to 7.0 wt.% across the selected parameter range. Differential scanning calorimetry revealed that coating levels up to 7 wt.% Co elevate the solidus temperature, while decreasing the liquidus temperature, resulting in a narrower melting interval. Thermodynamic simulations confirmed these trends, showing suppression of borides and enhanced γ/γ′ stability where γ denotes the Ni-rich face-cantered cubic matrix phase and γ′ represents the ordered Ni₃(Al,Ti)-type strengthening phase with increasing cobalt content. EDS mapping of coated powder showed continuous cobalt distribution at the particle perimeter. Overall, the results provided a quantitative basis for linking coating parameters to cobalt incorporation and corresponding modifications in melting behaviour.
Copyright (c) 2026 Tansu Göynük, İshak Karakaya https://creativecommons.org/licenses/by/4.0
Photocatalytic, electrochemical and photoelectrocatalytic degradation of the reactive dye Turquoise Tiafix R2G using LaFeO3 perovskite
In this study, the photocatalytic, electrochemical and photoelectrocatalytic performance of lanthanum ferrite (LaFeO₃) toward the degradation of the dye Turquoise Tiafix R2G was investigated. LaFeO₃ was synthesized via a sol-gel route and characterized by XRD, N₂ adsorption (BET) and SEM, confirming its perovskite structure. Photolysis experiments indicated that the dye is highly photostable under the irradiation conditions employed. In photocatalysis, different LaFeO₃ loadings (0.1, 0.2 and 0.3 g L⁻¹) were tested under a 100 W halogen lamp, with 0.3 g L⁻¹ providing the highest removal, although the process remained limited by electron-hole recombination. In heterogeneous electro-oxidation with LaFeO₃ in suspension, current densities of 10, 15 and 20 mA cm⁻² were applied; 15 mA cm⁻² afforded the best compromise between activity and stability, significantly increasing the dye oxidation rate. The simultaneous application of irradiation and current in the photoelectrocatalytic process led to the highest efficiency, achieving approximately 95% degradation within 60 min. These results demonstrate a clear synergistic effect between photocatalytic reactive oxygen species generation in the LaFeO₃ suspension and electrochemical oxidant generation at the anode, resulting in a more effective oxidative environment. Thus, the optimized photoelectro­catalytic condition (0.3 g L⁻¹ LaFeO₃ and 15 mA cm⁻²) is a promising strategy for the treatment of effluents containing industrial dyes.
Copyright (c) 2026 Jonh Yago Erikson Santos, Rebeca E. S. Barros, Katlin I. B. Eguiluz, Patrícia M. Pimentel, Rosane M. P. B. Oliveira, Giancarlo R. Salazar-Banda https://creativecommons.org/licenses/by/4.0
Ultrasound-assisted alkaline water electrolysis in a membrane-separated H-type cell: a device-scale benchmark under galvanostatic operation
Reported benefits of ultrasound in alkaline water electrolysis remain difficult to compare because apparent gains can be influenced by thermal drift, inconsistent energy-accounting boundaries, and differences in reactor geometry. Here, we provide a conservative benchmark of ultrasound-assisted alkaline water electrolysis in a small, membrane-separated H-type cell operated galvanostatically in 2.0 M NaOH at 0.6, 0.8, and 1.0 A. Silent electrolysis, low-amplitude ultrasound, and high-amplitude ultrasound were compared over a unified 300 s window while maintaining the catholyte near the hydrogen-evolving electrode at 32-34 °C. Under these tightly controlled conditions, ultrasound produced small but consistent device-internal effects: collected H₂ output increased by about 1 %, purity-corrected Faradaic efficiency remained essentially unchanged at around 66 %, and the average cell voltage decreased by approximately 0.09 to 0.29 V, corresponding to a 1.6 to 2.1 % reduction in specific electrical energy consumption on an electrolyzer-electrical basis. These results are most consistent with relief of bubble-related and near-electrode transport losses, rather than the emergence of a new reaction pathway or a large change in intrinsic reaction kinetics. At 1.0 A, varying ultrasonic amplitude further indicated a practical operating window in which moderate ultrasound minimized electrolyzer-electrical SEC, whereas higher amplitude maximized instantaneous hydrogen throughput but caused visible graphite-anode degradation in the present geometry. The present results, therefore, do not establish a full-system energy benefit; instead, they provide a conservative, device-internal benchmark for assessing when, and to what extent, ultrasound may remain useful under rigorously controlled conditions. Future studies should extend this framework to reduced-gap cells, advanced electrodes, and full system-level accounting that explicitly includes acoustic power and balance-of-plant loads.
Copyright (c) 2026 Zeng ChenHongWen, Teoh Yew Heng, Heoy Geok How, Mohamad Yusof Idroas, Thanh Danh Le https://creativecommons.org/licenses/by/4.0
Bismuth molybdate nanostructure modified carbon paste electrode for voltammetric sensing of levodopa in the presence of acetaminophen
In the present work, a voltammetric sensor for levodopa (L-DOPA) was fabricated based on Bi2MoO6 nanostructure-modified carbon paste electrodes (Bi2MoO6/CPE). Bi2MoO6 nanostructures were synthesized via the solvothermal procedure and characterized by X-ray diffraction pattern. The Bi₂MoO₆/CPE exhibited an enhanced current response for L-DOPA, which we attribute to the good electrocatalytic activity of the Bi2MoO6 nanostructures. Furthermore, the Bi2MoO6/CPE sensor was applied to determine L-DOPA in the presence of acetaminophen (ACT). The anodic peaks for L-DOPA and ACT were well-resolved in their mixture, enabling their simultaneous determination. The voltammetric measurements at pH 7.0 revealed distinct anodic peaks for the two analytes, located at approximately 350 mV (L-DOPA) and 530 mV (ACT). Using differential pulse voltammetry, a linear correlation was observed between the oxidation peak current and L-DOPA concentration over the range 0.02 to 590.0 μM. The limit of detection was determined to be 0.009 μM. The practical applicability of the Bi2MoO6/CPE sensor was successfully demonstrated through the assay of L-DOPA and ACT in real samples.
Copyright (c) 2026 Abdul Amir H. Kadhum , Ahmed J. Allami, Hajir M. Ali, Huda Hadi Nameh https://creativecommons.org/licenses/by/4.0
Silver-doped TiO2 nanotube array nanosensor for gallic acid detection: active surface and electrochemical enhancement
The development of electrochemical methods for the detection of phenolic compounds is a highly active area of research, motivated by their simplicity, efficiency and versatility of application. This work presents the synthesis and characterization of an electrochemical nanosensor for the detection of gallic acid, a phenolic compound of nutraceutical and analytical relevance. The nanosensor is based on a titanium electrode superficially modified with a titanium oxide nanotube array doped with silver (Ag-TNA). It was synthesized via electrochemical anodization and characterized using scanning electron microscopy, X-ray diffraction, Raman spectroscopy, and X-ray photoelectron spectroscopy. The electrochemical properties and gallic acid sensing capability were tested using electrochemical impedance spectroscopy and cyclic voltammetry. The results confirmed the obtention of an electrode surface composed mainly of titanium oxide in the anatase phase with the presence of oxygen vacancies. Metallic silver was found incorporated in interstitial form, while the ionic silver state is present superficially. The presence of silver promotes crystallinity and active surface area of the electrode. The Ag-TNA nanosensor displays two oxidation peaks in response to gallic acid; the first peak, registered at 1.3 V vs. Ag/AgCl, was used for the detection method developed in a linear range of 565 to 4663 µM (R2= 0.997). Key analytical parameters were calculated, obtaining a sensitivity of 118 μA mM⁻¹ cm⁻², limit of detection of 13.2 μM, limit of quantification of 43.9 μM, and relative standard deviation of 3.4 and 4.5 % in repeatability and reproducibility tests, respectively. The sensor exhibited selectivity toward glucose and ascorbic acid, common interferents.
Copyright (c) 2026 Zaira Mora-Mora, Ma. Guadalupe Garnica-Romo, Héctor Eduardo Martínez-Flores, Juan José Alvarado-Gil, Leandro García-González https://creativecommons.org/licenses/by/4.0
Synthesis of Fe-based metal organic framework/MWCNTs for modification of glassy carbon electrode: application in the efficient stripping voltammetric determination of Pb(II) ions
In the present work, a composite of multi-walled carbon nanotubes (MWCNTs) and Fe-based metal-organic framework (Fe-MOFs) has been prepared and utilized to construct modified glassy carbon electrodes (MGCE) by the drop-casting method. The MWCNTs/Fe-MOF-MGCE was used as a simple and sensitive electrochemical sensing platform for detecting Pb(II) ions. It has been found that modifying the GCE surface with MWCNTs/Fe-MOF significantly increased the Pb(II) stripping peak current. The effect of different parameters and conditions, such as pH of the supporting electrolyte solution, accumulation time and accumulation potential on the designed sensor's response, were evaluated. Square-wave anodic stripping voltammetry is used for the sensitive determination of Pb(II). Under optimal conditions, a linear dependence was observed between the anodic peak current of Pb(II) and its concentration in the range of 0.4 to 240.0 ng mL-1. The limit of detection of the MWCNTs/Fe-MOF/MGCE was determined to be 0.1 ng mL-1 for Pb(II) determination. Finally, the designed method was successfully used to determine Pb(II) ions in water samples, with high recoveries and low relative standard deviations, showing its applicability.
Copyright (c) 2026 Rouaa A Muften, Mayada Hadi Al-qassi, Raed Muslim Muhibes https://creativecommons.org/licenses/by/4.0
Application of MWCNTs/Uio-66(Zr)-NH₂ MOF modified electrode for anodic stripping determination of Cu(II) in water samples
In this research, a procedure was developed for the detection of Cu(II) ions in water using a glassy carbon electrode modified with a nanocomposite of multi-walled carbon nanotubes and a zirconium-based metal-organic framework (MWCNTs/Uio-66(Zr)-NH₂ MOF/GCE). The analysis was performed by differential pulse anodic stripping voltammetry. The excellent sensitivity of the created sensor (MWCNTs/Uio-66(Zr)-NH₂ MOF/GCE) for Cu(II) determi­nation is attributed to the synergy between the strong chelating ability of the terminal amino groups (-NH₂) on the Uio-66 (Zr)-NH₂ MOF for metal ions and the extensive surface area provided by the MWCNTs. The key parameters influencing the stripping current res­ponse of Cu(II), namely, pH, accumulation potential, and accumulation time, were syste­ma­tically studied and optimized. Under optimal conditions, the stripping peak current of Cu(II) ions exhibited a linear relationship with concentration over the range of 0.001 to 10.0 μM. The limit of detection for Cu(II) ions was calculated to be 0.0005 μM. Finally, the MWCNTs/Uio-66 (Zr)-NH₂ MOF/GCE sensor was employed to determine Cu(II) ions in real water specimens, yielding acceptable recovery rates.
Copyright (c) 2026 Mais A. Mohammed, Mustafa Abdul-Sattar Ibrahem Al-Hamid, Dalia M. Jamil, Shaimaa B. Al-Baghdadi https://creativecommons.org/licenses/by/4.0
Graphene oxide/NiO nanocomposite-modified carbon paste electrode for the simultaneous detection of carmoisine and tartrazine as two azo dyes in food samples
A carbon paste electrode (CPE) was modified with a graphene oxide (GO)/NiO nanocomposite (GO/NiO/CPE) and used as the working electrode for the voltammetric analysis of carmoisine. In the oxidation of carmoisine, the GO/NiO/CPE showed increased electrocatalytic activity. With a detection limit of 0.1 μM under ideal conditions, the oxidation peak currents of carmoisine were linearly proportional to its concentration over the range 0.3 to 500.0 μM. Additionally, the GO/NiO/CPE showed good efficacy in detecting carmoisine even in the presence of tartrazine, suggesting that both chemicals might be determined simultaneously. The GO/NiO/CPE was appropriate for the simultaneous detection of carmoisine and tartrazine using differential pulse voltammetry because the oxidation peak potentials of the two azo dyes were adequately separated by 420 mV.
Copyright (c) 2026 Fares A. Yasseen, Ali Obaid Imarah, Rasha Faris Hadi, Huda Hadi Nameh https://creativecommons.org/licenses/by/4.0
Phenolic-rich plum peel extract–mediated synthesis of gold nanoparticles for electrochemical detection of Pb(II)
Gold nanoparticles (AuNPs) were successfully synthesized using plum peel (Prunus salicina) extract as a green reducing and stabilizing agent, offering an environmentally benign approach to nanomaterial preparation. Optimization showed that a precursor-to-extract volume ratio of 7:3 with 80 mL maceration solvent yielded the most stable colloid, evidenced by a surface plasmon resonance peak at 534.9 nm. Fourier transform infrared spectroscopy analysis indicated that phenolic -OH and aromatic C=O/C=C functional groups played a key role in Au(III) reduction and nanoparticle stabilization. Transmission electron microscopy images revealed predominantly spherical AuNPs with an average size of 13.16±4.9 nm, while a zeta potential of -33.4 ± 0.2 mV confirmed colloidal stability. The optimized AuNPs were drop-casted onto pencil graphite electrodes (PGE) to fabricate a low-cost electrochemical sensor for Pb(II) detection. The modified electrode exhibited a 50.7% enhancement in the Pb(II) peak current compared to bare PGE. Differential pulse voltammetry showed linearity over 25 to 200 ppb (R² = 0.9921), a sensitivity of 0.0172 µA ppb⁻¹, and a limit of detection of 18.95 ppb, below the Indonesian regulatory limit for surface waters. Scanning electron microscopy-energy dispersive X-ray spectroscopy mapping confirmed uniform AuNPs distribution, sup­porting improved electron-transfer behaviour. Overall, this work highlights the potential of fruit-peel-derived AuNPs for a portable and sustainable detector.
Copyright (c) 2026 Yohanes Susanto Ridwan, Muhammad Fajar Arzena Nurhadi, Santhy Wyantuti, Rafa Radithya Swara, Athanasia Amanda Septevani , Fitri Khoerunnisa , Irkham, Yeni Wahyuni Hartati https://creativecommons.org/licenses/by/4.0
Next-generation electrochemical sensors and biosensors for paracetamol detection: emerging trends and future perspectives
Paracetamol (PCT), a widely used drug, is increasingly present in environmental and pharma­ceutical samples, raising the need for monitoring and control. Electrochemical sensors (ES) and electrochemical biosensors (EBS) have proven to be promising analytical methods for PCT detection. This review aims to provide a comprehensive comparison of ES and EBS for PCT detection, highlighting advances in electrode modification strategies, signal amplification approaches and biological recognition elements. The reported limits of detection range from the picomolar level (≈10 pM in immunosensors) to the micromolar range, varying with material design and recognition element. Carbon-based and metal/metal oxide materials enhance sensitivity through improved electron transfer and catalytic activity. Enzymatic and antibody-based sensors provide higher selectivity. The drawbacks of enzymatic and non-enzy­matic biosensors are low long-term stability, enzyme degradation, lack of interference testing in different sample matrices and lack of standardized protocols. Antibody- and DNA-based electrochemical platforms for PCT are under-analysed fields compared to nanoma­terial-driven approaches. This review also identifies current challenges, the need for stan­dar­dised protocols and key drawbacks of ES and EBS systems. Future perspectives for the deve­lopment of hybrid, portable, miniaturized, and real-time monitoring systems are further outlined.
Copyright (c) 2026 Santhanalakshmi Nagendran, Jih-Hsing Chang, Mohanraj Kumar, Prakash Natrajan https://creativecommons.org/licenses/by/4.0
Comparative study of 2D perovskite cathodes: impact of organic cation variation on electrochemical performance in lithium-ion batteries
In this study, two organic-inorganic hybrid perovskites, butylammonium copper chloride (BACC) and methylammonium copper chloride (MACC), were synthesized and evaluated as feasible active cathode materials for lithium-ion batteries. Both compounds were structurally and morphologically characterized using X-ray diffraction, scanning electron microscopy and infrared spectroscopy, revealing high crystalline structures and well-defined morphologies consistent with long-range order and unique features of conversion materials. The electrochemical performance of synthesized compounds as cathodes was assessed through cyclic voltammetry and galvanostatic charge/discharge measurements. Butylammonium copper chloride, with formula (C4H12N)2CuCl4, exhibited a remarkable specific discharge capacity of 200 mAh g-1 at 20 mA g-1 with capacity retention close to 65 %. Meanwhile, methylammonium copper chloride (CH3NH3)2CuCl4 delivered a specific capacity of 160 mAh g-1 at 20 mA g-1, maintaining 90.2 % capacity retention. Post-cycling XRD analysis was carried out on the cathodes after 100 cycles of operation at 50 mA g-1, providing evidence of structural changes during battery operation. These structural transformations account for the gradual capacity fading observed during prolonged cycling and demonstrate that a Coulombic efficiency close to 100 % does not necessarily imply structural reversibility. Overall, the results indicate that BACC and MACC should be regarded as model systems for fundamental studies of copper electrochemical chemistry in halogenated hybrid perovskites, rather than as competitive cathode materials for practical lithium-ion battery applications.
Copyright (c) 2026 Alfredo Romero-Contreras, Nora Aleyda García-Gomez, Eduardo Sanchez Cervantes https://creativecommons.org/licenses/by/4.0
Validation of a low-cost carbon screen-printed electrode platform: a statistical approach
Electrochemical sensors have gained increasing attention for their high selectivity and sensitivity. Screen-printed electrodes (SPEs) are particularly attractive as low-cost, disposable, and scalable platforms that enable miniaturized electrochemical cells and field-deployable measurements. Here, we report a low-cost and easily fabricated carbon paste -SPE platform consisting of a 3D-printed acrylonitrile butadiene styrene body filled with carbon paste (graphite/mineral oil, 70:30) and a silver-ink pseudo-reference electrode. The device was evaluated using potassium ferricyanide (5.0 mmol L-1 in 0.5 mol L-1 KCl) as a redox probe. The ipa/ipc ratio was close to unity, while the peak-to-peak separa­tion (ΔEp≈949 mV) indicated kinetic/ohmic contributions typical of composite carbon-based printed electrodes. A linear relationship between the corrected anodic peak current (iap) and the square root of the scan rate (v1/2) yielded an electroactive area of 0.485 cm², substantially larger than the geometric area, consistent with surface heterogeneity/porosity. Statistical validation by ANOVA confirmed good repeatability and reproducibility (p > 0.05, 95 % confidence). Overall, the proposed CP-SPE provides a robust and reproducible low-cost platform with strong potential for voltammetric sensing applications.
Copyright (c) 2026 Juliene Morais de Faria, Thomaz Henrique da Cunha Reis, Larissa Silva de Azevedo, Caio Henrique Pinke Rodrigues, Aline Thaís Bruni, Marcelo Firmino de Oliveira https://creativecommons.org/licenses/by/4.0
Scaling-ion removal from high-salinity produced water via sono-electrocoagulation: interplay of floc microstructure and electrochemical surface activity
Produced water from oil fields contains complex dissolved organic and inorganic species, including Ca²⁺, HCO₃⁻, and CO₃²⁻, which induce CaCO₃ scaling and hinder waterflooding operations. This study investigated the performance of electrocoagulation (EC) and ultrasonic-assisted electrocoagulation (sono-EC) for treating native produced water from Indonesian oil fields, focusing on scaling ion removal, floc structural characteristics, and hydrogen evolution. Experiments were conducted at pH 5, 7 and 9 using Al-SS316 electrodes under constant current conditions, with intermittent sonication applied to enhance Al³⁺ release and suppress electrode passivation. The results demonstrated that pH 7 provides optimal conditions for the formation of stable amorphous Al(OH)₃ flocs. Scanning electron microscopy analysis revealed a porous lamellar morphology that promotes ion adsorption and co-precipitation, resulting in the highest removal efficiencies of Ca²⁺, HCO₃⁻ and chemical oxygen demand (COD). Sonication further enhanced process performance by inducing cavitation-driven micro-mixing, accelerating floc growth, and increasing hydrogen evolution. Brunauer-Emmett-Teller and Barrett-Joyner-Halenda analyses confirmed pro­nounced pH-dependent differences in floc porosity and surface characteristics, which mechanistically explained variations in ion capture behaviour. Overall, the sono-EC operated at neutral pH offers an effective strategy to mitigate scaling potential, while hydrogen evolution is used as an electrochemical indicator of cathodic surface activity.
Copyright (c) 2026 Reno Pratiwi, Kartika Fajarwati Hartono, Maman Djumantara, Dina Asmaul Chusniyah, Wiwik Dahani, Tiur Elysabeth https://creativecommons.org/licenses/by/4.0
Rapid and sensitive electrochemical determination of phosphate ions using a multi-walled carbon nanotube carbon paste electrode
Phosphates are widely used in food as texture modifiers, preservatives and flavour enhan­cers, while excessive intake may negatively affect human health and the environment. Consequently, there is a growing demand for low-cost, portable, and reliable tools for phosphate monitoring in food and water samples. In this work, an electrochemical sensor based on a multi-walled carbon nanotube (MWCNT) modified carbon paste electrode (CPE) was developed for phosphate determination. Phosphate detection was based on the electrochemical reduction of an electroactive phosphomolybdate complex formed in acidic medium (50 mM sulfuric acid). Key analytical parameters, including solution acidity and complexation time, were optimized to enhance sensor performance. Carbon nanotube modification significantly enhanced the electrochemical response. While the bare CPE shows weak, poorly defined redox peaks due to limited electron transfer and low surface area, MWCNT-modified CPE exhibits well-defined peaks with ~6-fold higher current, reflecting improved sensitivity, faster electron transfer, and better peak separation. Using square-wave voltammetry, the sensor exhibited a linear response in the phosphate concen­tration range of 3.1 to 21.7 mg L⁻¹, with a detection limit of 0.03 mg L⁻¹ and a response time of approximately 10 s. The sensor was successfully applied to real sausage samples, yielding recoveries of 94.6 to 97.2 % with relative standard deviation values below 5 %. The presented MWCNT-CPE sensor provides a cost-effective, portable and simple device for fast and reliable in situ detection of phosphate in food and water samples.
Copyright (c) 2026 Qendresa Istrefi, Nevila Broli, Loreta Vallja, Sonila Duka, Sadik Cenolli https://creativecommons.org/licenses/by/4.0
Transition metal oxide-modified carbon electrodes: A comprehensive review on surface area modulation and Randles-Ševčik electrochemical insights
The exceptional catalytic properties of transition metal electrocatalysts, including high activity, stability, electronic properties, and selectivity in various electrochemical processes, make them essential in electrochemistry. The combination of these electrocatalysts with carbon-based interfaces improves their performance by providing increased electrical conductivity, greater surface areas, and robust structural support. Expanding the electrode area by offering more active sites for the processes and boosting efficiency increases the catalytic activity. This review emphasizes the importance of maximizing electrode surface area and the variations in transition metal oxides (TMOs) with carbon interfaces to achieve excellent performance in various electrochemical applications. Special focus is given to the Randles-Ševčik equation as a fundamental tool for evaluating the electroactive surface area and charge transfer properties of TMO-modified electrodes. Furthermore, the review discusses the influence of structural modifications on catalytic performance. By summarizing recent advancements and challenges, this study aims to provide a comprehensive under­standing of the potential of transition metal oxides as efficient electrocatalysts for sustainable energy and sensing applications.
Copyright (c) 2026 Kruthika Manohara Sakamma, Gururaj Kudur Jayaprakash https://creativecommons.org/licenses/by/4.0
Synergistic effects of NH2-MIL-101(Fe) metal-organic framework and Pd nanoparticles for sensitive determination of norepine­phrine in the presence of acetaminophen
An electrochemical sensor based on an amino-functionalized iron NH2-MIL-101(Fe) metal-organic framework (MOF)/Pd nanoparticles (NPs) composite-modified screen-printed elec­trode (SPE) is prepared for the simultaneous determination of norepinephrine (NEPI) and acetaminophen (ACP). The NH2-MIL-101(Fe) MOF/Pd NPs/SPE electrochemical sensor shows a significant enhancement in the response peak current of NEPI, as compared to bare SPE. This suggests that the unique features of NH2-MIL-101(Fe) MOF/Pd NPs composite-mo­di­fied SPE improve the electro­catalytic oxidation of NEPI. Such a synergistic effect bet­ween NH2-MIL-101(Fe) MOF and Pd NPs results in a significant enhancement in the res­pon­se, where the MOF's high surface area combines with the high electron-transfer rate and the abundance of catalytically active sites afforded by the Pd NPs. The differential pulse vol­tam­metry (DPV) method was obtained for quantitative determination of NEPI and high sen­sitivity was observed in NEPI determination with the calibration slope of 0.0327, µA µM-1. The developed NH2-MIL-101(Fe) MOF/Pd NPs/SPE sensor presents a low limit of detection of 0.007 µM toward NEPI determination. The developed NH2-MIL-101(Fe) MOF/Pd NPs/SPE sensor shows a good catalytic activity for the oxidation of NEPI and ACP, with anodic peak potentials of 360 and 550 mV, respectively. The separation of anodic peak potential is sufficient to enable simultaneous determination. Finally, the suggested sensing platform has confirmed suitable for the simultaneous determination of NEPI and ACP in real samples (pharmaceutical formulations and urine samples), achieving recovery values ranging from 97.1 to 104.4 % with relative standard deviations ≤3.6 %.
Copyright (c) 2026 Shaimaa A. Jadoo, Azhar Farooq, Israa M Radhi, Hanadi A. Fadhil, Juman A. Naser https://creativecommons.org/licenses/by/4.0
Parameter selection of cerium oxide anodic electrodeposition on screen-printed carbon electrodes using response surface methodology for nucleic acid based biosensors
Screen-printed carbon electrodes (SPCEs) modified with cerium oxide (ceria) have attracted considerable attention due to their outstanding stability and electrochemical performance, making them promising candidates for sensor and biosensor applications. However, the anodic electrodeposition of ceria on SPCEs involves multiple parameters that may strongly influence film formation and electrochemical behaviour, yet these factors have not been systematically optimized. This study aimed to determine and optimize the key parameters affecting anodic electrodeposition of ceria on SPCEs using cyclic voltammetry (CV) and res­ponse surface methodology. All four main parameters, namely UV irradiation time, distance between the SPCE and UV lamp, cerium nitrate concentration and the number of CV cycles, significantly influence the anodic electrodeposition process of ceria, shown by the statistical analysis (p <0.05). The optimized SPCE/ceria electrode exhibited improved electrochemical performance, with an average peak current of 44.158 μA and a relative standard deviati-on (RSD) of 2.68 %. This optimized SPCE/ceria was subsequently tested for guanine oxide­tion using differential pulse voltammetry with an immobilized RNA probe and produced good repeatability with an RSD value of 2.37 %. The findings underscore the importance of parameter optimization to enhance the reproducibility and sensitivity of SPCE/ceria electrodes, demonstrating their strong potential for future biosensing applications.
Copyright (c) 2026 Clianta Yudin Kharismasari, Ari Hardianto, Muhammad Ihda Hamlu Liwaissunati Zein, Salma Nur Zakiyyah, Yeni Wahyuni Hartati, Irkham https://creativecommons.org/licenses/by/4.0
Mango peel extract as a green inhibitor in the corrosion of reinforced concrete
Chloride-induced corrosion of reinforcing steel embedded in concrete is a problem that causes the elements to lose their physical and mechanical properties and can lead to premature failures in civil works. This research article analyses the effectiveness of the green corrosion inhibitor in cement paste through the ethanolic extract of mango peel. The materials were dosed with the inhibitor added to the mixing water and the mechanical properties of the material were analysed by manufacturing cylindrical test specimens. To understand the corrosion phenomena, cubic samples were prepared and immersed in a 3 % sodium chloride (NaCl) solution for 365 days, simulating a highly aggressive chloride-ion environment. Electrochemical techniques such as half-cell potential (HCP), electro­chemical noise (EN), linear polarization resistance (LPR) and electrochemical impedance spectroscopy (EIS) are applied. The experimental results showed that the green corrosion inhibitor reduced the mechanical properties of concrete by 21.28 % compared to the blank, but a positive effect was observed in the corrosion evaluation. Initially, the inhibitor delayed the onset of corrosion, as indicated by high electrochemical noise and linear polarization resistance values due to the formation of a film of organic compounds present in the inhibitor extracts that acted on the active sites on the steel surface.
Copyright (c) 2026 Alejandro Flores-Nicolás, Elsa Carmina Menchaca-Campos, Mario Flores-Nicolás https://creativecommons.org/licenses/by/4.0
Exploring the inhibitory performance of expired moxifloxacin and norfloxacin on copper corrosion in saline environment
The reuse of expired drugs has become a challenge to maintain environmental clean-liness and achieve economic benefit. In this report, two expired drugs, moxifloxacin and norfloxacin, were used as inhibitors for copper corrosion in 3.5 % NaCl solution at different temperatures using several experimental approaches including chemical, electrochemical and spectroscopic techniques. The interaction of these two molecules on the copper surface was also inspected using different adsorption models. Using a dose of 500 mg L-1 of these drugs at 298 K, maximum inhibition efficiencies (IE) of 88.7 and 85.2 % were estimated from the potentiodynamic polarization technique for Mox and Nor, respectively., confirming that they can be considered as promising and effective inhibitors. The IE values were enhanced with increasing drugs doses and reduced with rising temperature. The higher IE is due to the strong adsorption of these molecules on the copper surface and such adsorption is physical in nature and follows the Langmuir adsorption isotherm. This is due to their unique chemical structures as they contain a number of functional groups. Polarization experiments confirmed that the drugs were tuned to behave as mixed-type inhibitors with an anodic predominance. All thermos¬dynamic and kinetic parameters were calculated and discussed in details, and the inhibition mechanism is proposed. All experimental results obtained by different techniques were in agreement with each other.
Copyright (c) 2025 Journal of Electrochemical Science and Engineering https://creativecommons.org/licenses/by/4.0
Porcine gelatine detection via electrochemical immunosensors utilizing green-synthesized cerium oxide nanoparticles from orange peel
Maintaining the safety and proper labelling of food products is vital for communities around the world. One of the primary concerns in food safety is the unintentional presence of porcine derivatives such as gelatine in food products. This issue could affect the labelling accuracy of food products, religious dietary observances, regulatory compliance, and public health. Electrochemical immunosensors address this issue by rapidly, portably, and especially with high sensitivity, detecting porcine gelatine. The electrode was modified with CeO2 nanoparticles (NPs) synthesized via a green method using orange peel extract, which enhanced the immobilization of the bioreceptor on the electrode surface. Orange peel extract contains secondary metabolites that can act as stabilizing agents and prevent agglomeration during the synthesis process. The synthesized CeO2 NPs show a cube morphology, producing an average particle size of 12 nm with 77.31 % crystallinity. The performance of green synthesized CeO2 NPs modified electrode are successful for detecting porcine gelatine in solution and commercialized gelatine product, resulting in a limit of detection of 3.53 ppm. These results show the potential of green-synthesized CeO2 NPs for an electrochemical immunosensor for detecting porcine products.
Elisabeth Nasya Dominika Setyawati Putri
Copyright (c) 2025 Rafa Radithya Swara, Nazwa Alya Zahra, Dea Hasna Tsary, Biyas Aurora Nania Nevada, Elisabeth Nasya Dominika Setyawati Putri, Salma Nur Zakiyyah , Yohanes Susanto Ridwan, Yeni Wahyuni Hartati, Irkham Irkham https://creativecommons.org/licenses/by/4.0
Carbon paste electrode modified with Bi2WO6 nanosheets and ionic liquid: voltammetric assay of dasatinib in the presence of doxorubicin as two anticancer drugs in pharmaceutical and biological samples
The main goal of this effort is to create an innovative electrochemical sensor for dasatinib detection in the presence of doxorubicin. It was possible to create Bi2WO6 nanosheets easily. The electrochemical performance of the Bi2WO6 nanosheets/ionic liquid modified carbon paste electrode (Bi2WO6/IL/CPE) was examined in relation to dasatinib detection. Additionally, compared to the unmodified electrode, Bi2WO6/IL/CPE demonstrated good electrocatalytic activity for dasatinib oxidation. Under ideal circumstances, the current sensor (Bi2WO6/IL/CPE) was investigated using differential pulse voltammetry (DPV). The results showed a linear dynamic range as wide as 0.1-230.0 μM and a limit of detection of 0.05 μM. Additionally, in well-spaced anodic peaks, the Bi2WO6/IL/CPE sensor showed good analytical efficiency for detecting dasatinib in the presence of doxorubicin. This sensor showed two separate peaks for the oxidation of doxorubicin and dasatinib, per the DPV data. Furthermore, the voltammetric measurement of dasatinib and doxorubicin in biological and pharmaceutical specimens was investigated using the Bi2WO6/IL/CPE.
Copyright (c) 2025 Mayada Hadi Al-qassi, Wisam Hashim Baqer, Abdul Amir H. Kadhum https://creativecommons.org/licenses/by/4.0
Self-healing efficiency of ceria-doped Zn-Co coatings: Insights into particle-free versus biphasic plating baths
Achieving the superior properties of nanocomposite materials involves addressing several challenges, particularly the agglomeration of nanoparticles in the plating bath. This study focuses on the electrodeposition and characterization of Zn-Co-CeO2 composite coatings using a particle-free plating bath, an effective strategy for mitigating agglomeration. For comparison, the composite coatings were also deposited from a traditional biphasic plating solution. The coatings were deposited galvanostatically at various current densities. Scanning electron microscopy revealed that using a particle-free plating solution in conjunction with lower current densities enhanced the compactness and the overall quality of the coatings. Lower current densities favoured the codeposition of particles, as indicated by energy-dispersive X-ray spectroscopy results. Notably, the coatings produced from the particle-free bath exhibited significantly improved corrosion resistance and durability in chloride-rich environments, attributed to their self-healing properties, as shown by electrochemical impedance spectroscopy.
Copyright (c) 2024 Journal of Electrochemical Science and Engineering https://creativecommons.org/licenses/by/4.0
Improved performance of nitrate extended gate field effect transistor sensor through deposition of polymer layer at various withdrawal speeds using dip coating method
In this study, a nitrate Extended Gate Field Effect Transistor (EGFET) sensor has been deposited with polyaniline (PANI) using a dip coating method by varying the withdrawal speed parameter at a range of 1 to 7 mm/s to improve the detection and stability of the sensor that uses zinc oxide (ZnO) as a sensing material, which lacks sensitivity and stability in detecting nitrate. The sensor was characterized by analysing its surface morphology, light absorption, and wettability level. The sensitivity and linearity of the sensors were evaluated using EGFET measurements, which showed that the threshold voltage changes when the sensor interacts with the analyte. The results obtained by comparing ZnO/indium tin oxide film and PANI/ZnO film show that PANI helps to improve sensor performance, and the best parameter setup to deposit PANI was at 2 mm/s withdrawal speed, resulting in a super-Nernstian response with a high sensitivity of 78.90 mV/dec and close to 1 linearity. The film showed excellent long-term stability in detecting nitrate in a 50-ppm nitrate solution, with the lowest drift rate at 0.1278 V/h. The dip coating method, using a 2 mm/s withdrawal speed, appears to be effective for fabricating PANI as a polymer layer for nitrate sensors.
Electrodeposition of Ni-Co thin films from ammonia-chloride electrolyte
This study presents the research results on the co-deposition of nickel and cobalt from an alkaline electrolyte containing glycine. For this purpose, cyclic and linear polarization curves of co-deposition were obtained at various cobalt concentrations, different poten-tial sweep rates, and electrolyte temperatures. It was established that the co-deposition process occurs anomalously, with the cobalt content in the deposited films exceeding that of nickel. The deposits obtained under optimal conditions contained 37.25 % Ni and 51.43 % Co. The study of the effect of the potential sweep rate on the co-deposition process of nickel and cobalt revealed a linear relationship between the current peak value and the square root of the potential sweep rate. This indicates that the initial stage of Ni-Co co-deposition is controlled by the diffusion of the metal ions to the cathode surface. When recording polarization curves on a rotating disk electrode at different rotation speeds, the relationship between the current peak value and the square root of the electrode rotation speed was also linear at relatively low rotation speeds. However, at higher rotation speeds, the process was controlled by electrochemical polarization. The co-deposition of Ni with Co was confirmed through X-ray diffraction, scanning electron microscopy and energy-dispersive X-ray spectroscopy analyses. The investigation of the catalytic activity of Ni-Co deposits in a neutral medium (0.5 M Na₂SO₄) demonstrated that the amorphous thin films, not subjected to annealing, exhibited the best electrocatalytic properties for the hydrogen evolution reaction. The Tafel slope was determined to be 118 mV dec-1.
Copyright (c) 2025 Aygun Oruj Zeynalova, Natavan Sharafaddin Soltanova, Ulviyya Magsud Gurbanova, Ruhangiz Gurmuz Huseynova, Akif Shikhan Aliyev, Dilgam Babir Tagiyev https://creativecommons.org/licenses/by/4.0
Influence of irradiation treatment on sensing performances of screen-printed electrodes aimed for doxorubicin monitoring
The subject of study is the development of nanosensors based on carbon nanotubes (CNTs) and polyaniline (PANI) aimed at effective detection and monitoring of doxorubicin - a chemotherapy drug used in the treatment of different types of cancer. The main goal is the design of nanosensors that provide precise and reliable detection and monitoring of doxorubicin, providing an effective approach to monitor drug levels during treatment. The research was carried out on the screen-printed electrodes (SPE) with a working electrode of commercial CNTs and PANI and their modification by irradiation with electron irradiation (50 kGy). The structural changes resulting from the e-beam irradiation were observed by scanning electron microscopy, Raman and FTIR spectroscopy, and thermogravimetric analysis. An electrochemical study employing cyclic voltammetry was done to characterize and test the performance of the nanosensors. Modification with electron irradiation was shown as an effective approach to improve the sensing characteristics of the studied SPE, resulting in a lower limit of detection for the modification. The irradiated SPEs exhibit a limit of detection of 12.674 µmol L⁻¹ for the modified multi-walled CNT (MWCNT) electrode and 12.712 µmol L⁻¹ for the modified PANI electrode, compared to 12.773 µmol L⁻¹ for the MWCNT and 12.712 µmol L⁻¹ for the PANI commercial electrodes.
Copyright (c) 2025 Perica Paunović, Iva Dimitrievska, Marija Katerina Paunović, Marija Mitevska, Anita Grozdanov https://creativecommons.org/licenses/by/4.0
Correlation between diffusion and kinetic behaviour of metal hydride battery: voltammetry and impedance analyses
The performance of metal hydride batteries depends on their electrochemical and kinetic behaviour, which varies with the state of charge (SoC). This study explores these characteristics in nickel-metal hydride batteries with A2B7 and AB5 electrodes, focusing on how SoC influences ion diffusion and charge transfer kinetics of the batteries. Electro¬chemical impedance spectroscopy and cyclic voltammetry (CV) were used to analyse these behaviours, while X-ray diffraction provided structural insights and scanning electron microscopy proposed morphological concepts. Results reveal a positive correlation between SoC and both diffusion and kinetic behaviour. The value of fitting resistances decreases as SoC increases, reaching a minimum at 100 % SoC, where hydrogen diffusion is optimized. CV data supports this phenomenon, showing a more negative peak cathodic current (Ip,c) at higher SoC, indicating improved kinetics likely due to enhanced ion availability. Additionally, voltage window analysis showed maximum hydrogen storage at 100 % SoC for AB5 and 50 % for A2B7. Structurally, larger particle sizes and crystallites at higher SoC correlate with increased hydrogen desorption capacity. A2B7 exhibited superior diffusion kinetics, while AB5 demonstrated better discharge behaviour, highlighting how SoC-dependent diffusion and kinetics impact Ni-MH performance.
Copyright (c) 2025 Ika Dewi Wijayanti, Delia Salsabila Putri, Farhan Dzikriansyah, Indra Sidharta, Sutikno Sutikno https://creativecommons.org/licenses/by/4.0
Improving the corrosion behaviour of Zn-Ni alloy coatings on 316 SS from chloride-sulfate bath by addition of triethanolamine or sucrose
Corrosion of Zn-Ni alloy coatings on stainless steel 316 SS in a chloride-sulfate bath with the addition of either triethanolamine or sucrose was examined. A constant cathode potential was used to deposit zinc-nickel alloys, while cyclic voltammetry and potentio-dynamic polarization were used to measure corrosion. In addition, scanning electron microscopy was utilized to analyse Zn-Ni alloy coating surface layers formed with¬out and with additives. The outcomes discovered that the corrosion resistance of Zn-Ni alloy coat¬ings in 3.5 % NaCl solution was highly influenced by adding triethanolamine or sucrose. Decreasing the Zn:Ni molar ratio led to an increase in corrosion resistance. All Zn-Ni alloy coatings were superior to pure Zn coating in their corrosion behaviour. The best result was found for potentiostatic electrodeposition of Zn-Ni alloy at the cathodic potential of -1.3 V vs. Ag/AgCl for 20 minutes in the presence of 0.335 M triethanolamine from a solution containing 0.02 M ZnCl2, 0.1 M NiSO4, 0.4 M H3BO4 and 1 M Na2SO4. For this Zn-Ni coating, a low corrosion rate of 0.00795 mm year-1 was observed at Ecorr = -0.5 V vs. Ag/AgCl and icorr= 0.535 µA cm-2. Scanning electron microscopy confirmed that this alloy has a granular structure with no cracks and a less porous structure. The new Zn-Ni alloy is superior in its properties in terms of corrosion resistance compared with those obtained in previous studies.
Copyright (c) 2025 Mothana Ghazi Kadhim Alfalah, Ali H. Abbar, Fatma Kandemirli https://creativecommons.org/licenses/by/4.0